


Sweet Teeth

by MUNASHIKU



Category: Death Note (Anime & Manga)
Genre: Brushing teeth, Kissing, M/M
Language: English
Status: Completed
Published: 2021-02-27
Updated: 2021-03-12
Packaged: 2021-03-18 11:15:35
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 2
Words: 2,631
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29733054
Author URL: https://archiveofourown.org/users/MUNASHIKU/pseuds/MUNASHIKU
Summary: L’s breath smells bad.
Relationships: L/Yagami Light
Kudos: 44





	1. Chapter 1

“Light-kun, I want another one.”

“Hell no.”

The older man leaned in closer, which caused Light to turn away in response.

“If you want another one, you’ll have to give up your commitment to sugar.”

L couldn’t help but whine, as the burden of giving up the source that fueled him in order to kiss Light was hard to ask of him.

“But I brush my teeth every day, Light-kun,” he tried.

“You’re smart enough to know that diets high in sugar will cause your breath to smell bad even if you brush every day,” Light responded, pushing L away gently. “It stinks even right now.”

L thought. “But if I brush after every single time I eat, then we’ll get nothing done. I’ll be spending all my time brushing.”

The brunette snorted in response. “Then maybe consider having normal meal times like the rest of us normal humans instead of grazing throughout the day.”

“Light-kun drives a hard bargain.”

.o

“Light-kun.”

“Stop, I’m trying to sleep and I know you’re eating cake.”

“You haven’t even tried to smell my breath yet.” The detective’s voice was getting closer.

“I’m not interested.”

Suddenly, he smelled a strong mint scent.

“What is that? I’ve never seen you eat anything mint-flavoured.”

“It’s gum—the solution to all of my dental hygiene problems.” Light could hear the grin through L’s voice. He turned in the bed just enough to see L, true to his word, chewing away.

“I swear, you have an oral fixation.” Light rolled his eyes and moved to lay back on his side.

“Can I have one now?”

Light sighed. “Fine.” He flopped himself over and let L have his kiss.

He was surprised to find it wasn’t as unpleasant as the first kiss, which was soured by not only the awful smell of sugar being digested by bacteria for fifteen hours in L’s mouth, but also the gross taste of said sugar caking every surface of his teeth. Since having chewed the gum, it seemed to have pulled a lot of that sugar grit off of the detective’s teeth, leaving smooth teeth to explore. Why he decided to trust the detective to French kiss him _again_ , he’s not sure, but he wasn’t kicking himself for it this time.

Suddenly, he felt L transferring the piece of gum he’d been chewing into his mouth. He yanked himself backwards, spitting out the chewed rubber onto the bed. L frowned.

“What the hell?!”

L glared at Light. “I was attempting to dispose of the gum so that I could get back to eating, but you decided to make a mess.”

“Fuck off, I’m not a trash can,” Light grunted, and turned to face toward the wall so hopefully he’d get some sleep tonight.

L sighed, staring at the chain between them. At least he now knew kissing was no longer off the table as long as gum was around.


	2. Chapter 2

**Summary for the Chapter:**

> An alternate timeline where L doesn’t brush his teeth at all, and Light is furious about it.

**Notes for the Chapter:**

> Didn’t think I’d add on to this story, but every time I get a popcorn kernel stuck in my teeth, I think of how it’ll rot my teeth away and that reminds me of L’s obnoxious sweet teeth. I wonder if dentists like to write fanfics of their fav characters getting a dental checkup LOL. Also I swear I don’t have a dental fetish It just feels really gud to brush my teeth not sexy good but it’s a satisfying sort of good

The first time Light smelled that awful breath was when L revealed himself to Light during the graduation ceremony. More than the shock of L being, well, L, was that unforgettable smell of something most foul. Light had to control his facial expression not to reveal his revulsion, because that expression may be mistaken as “It’s L!” and give a hint that he was indeed Kira.

The other students must not have been exposed to his breath because the detective preferred to breathe through his nose, but as soon as that mouth opened, whether to eat or speak, the odor leaked like a plague of death. He could tell they’d caught whiff of it when they leaned away while trying to keep a neutral face as well, but their eyes were watering.

No wonder he always kept a screen separating himself and the people he was talking to—if you were in the same room as him, you’d surely faint from that bad breath!

.o

Any time Light had to work with L, he tried to maintain as far a distance as possible in order to avoid having to be in proximity to that smell. In fact, he tried to keep questions down to simple yes or no questions so that it would minimize the amount of time L had to speak and thus further propagate that stinkhole he called his mouth. When he knew L was going to speak at length, he tried to move at a distance, even though L commented on Light’s peculiar behaviour, as _if_ he didn’t know his own hygiene might be a factor. _As if_. With breath that bad, even the most oblivious person had to be aware of it to some extent when they realized their friends or acquaintances started socially distancing themselves.

If anything, it was L’s weapon to keep Light from trying to do something suspect while close to L… Like stabbing him, or something.

.o

“Brush your teeth.”

“As we discussed it before, Light-kun, I will not participate in that. It is a waste of time.”

“Your teeth will fall out!”

“The foods I eat do not necessarily require teeth to consume.”

Light had a plan. A very simple but clever plan.

After he’d taken his shower and brushed his teeth, he held on to his toothbrush. L, ever astute and ever-watching, tensed when Light turned toward him.

Light really was going to sacrifice his toothbrush in order to alleviate the stink of his bed partner.

Of course, trying to force yourself on a person skilled in close combat wasn’t exactly the easiest thing to do. But somehow Light managed to gain the upper hand and they found themselves on the bed, chain wrapped oddly around them with Light kneeling above L, who was smashed on his back underneath with his arms trapped under Light’s knees and Light’s feet curled underneath and digging into his lower back so that L was forced into an awkward and painful arch. Light had seen this move in Brazilian Jiu-Jitsu, which was an effective restraint when the person below didn’t have a way to gain leverage with their own feet.

“You’re going to let me brush your teeth!”

“That’s very unhygienic, Light-kun, using your toothbrush to brush mine. Think of all the bacteria you’re donating to me.”

L tried bucking Light off, but Light clamped his knees tighter around L’s torso, causing the detective to hiss as it further pressed into his arms as well.

Light gripped L’s jaw with moderate strength, trying to pry his mouth open but failing to do so when the older man clenched his jaw shut. There was very little one could do to get a man’s mouth open aside from plugging their nose and keeping their mouth shut to prevent breathing, but all Light wanted to do was make some of the stink go away, so he settled for brushing the fronts of L’s teeth.

With one hand holding his jaw steady as well as keeping the lips parted, the other hand guided the toothbrush to gingerly touch L’s teeth. Light could feel L trying to jerk his head away, but that firm grip kept it from getting too far away.

“If you jerk around too much, I could end up damaging your gums from excessive friction. So stop.”

“I didn’t ask for this in the first place,” L responded through gritted teeth.

Light ignored him and wiggled the bristle tips gently left to right where the gums connected with the tooth before flicking the brush downward to get the plaque away from the gum line.

How had L’s teeth not become one giant block of tartar?

It was nearly a week since Light had been handcuffed to L for twenty-four hours a day, and Light had never seen L brush, not even once. Logically, with the amount of sugar L consumed, L should have had an insurmountable amount of tartar buildup on his teeth from lack of brushing, and yet when Light was peering into that mouth, it remained no less clean than an average mouth that missed brushing every other day but still brushed.

He was trying not to gag from having to smell L’s breath this close for a prolonged period of time.

“What are you doing?” L asked.

“What does it look like?” Light replied, beginning to move toward the back of L’s mouth, applying the same techniques gently. When he finished with the top row, he lightly circled the toothbrush over L’s gums.

“It feels weird,” L said.

“Weird as in pain? That’s probably because you don’t ever brush your teeth, which explains why your gums are red and inflamed,” Light chastised, continuing to massage the gums, which helped promote bloodflow, which was normally hindered due to the inflammation caused by bad oral hygiene. L sighed, almost in relief, which would have been a good sign for Light if not for the obvious acrid smell that followed.

“No… It feels good,” L murmured as Light began to work his bottom teeth. The detective seemed to lose that wild look in his eyes of an animal being trapped, eyes half-lidded and more relaxed. His muscles lost their tension and he even made a sound akin to one might make when getting a massage.

“If I’m hurting you, you can say it,” Light said as he bent closer despite the danger of his nose being obliterated.

“Hnn, good,” L responded. He paused before gingerly unclenching his jaw to let his tongue run over the fronts of his teeth.

“Feels smooth.”

“It could feel smooth every day if you’d just brush your damn teeth.” Light took the opportunity to shove the brush between the gap L made so that he could no longer close his jaw. L made a noise of discontent, but didn’t fight it as Light was allowed to brush the backs of L’s teeth. The worst of the odor proliferated as the mouth was now fully open.

In some ways, it felt a bit too intimate, seeing L’s tongue wiggle around the toothbrush like a lollipop, or brushing against his teeth that were cleaned by the bristles. Maybe even the sounds that L made, a bit _too_ pleased for his own good. Light ought to shove the toothbrush down the detective’s throat to get him to stop being so inappropriate in his displays of approval.

“Stop making those noises,” Light cringed, hoping that the older man would for the sake of Light’s own increased fixation on L’s mouth and the noises it could produce and the skills that tongue possessed from years of licking, licking, licking…

“But it feels so good when you rub my gums like that,” his victim retorted as best he could with an open mouth . Light couldn’t help but be fascinated by the saliva buildup that caused strands of spit to build and collapse wherever L’s tongue touched. Their faces were really close together.

“For Light-kun to complain about my breath, his face is awfully close to mine,” it’s like the detective had no ability to read the mood in the air, and Light was grateful, for he was a straight man and really didn’t need to be thinking about kissing a mouth that had the equivalent odor of a sewer.

“Shut up,” Light said, hurriedly scrubbing L’s tongue, which did wonders to dissipate the majority of the stink. Once he found the results satisfactory, he withdrew the toothbrush and pushed L away before climbing off of him.

“I’m going to need a new toothbrush,” he commented absently, tossing the toothbrush into a nearby trashcan.

“Light-kun should have thought of that before he decided to use it on someone else’s mouth,” L retorted. Light could see L’s mouth moving left and right, meaning his tongue was definitely checking out the clean surfaces.

“At least scrub your tongue with something. That’s what a lot of stink comes from—people not brushing their tongue.”

“I’m still deciding whether I like this change in my mouth or not,” was the despondent reply.

“We’re going to go through this every day if you refuse to brush.”

“I’d like to see Light-kun try that if he is not given another toothbrush.”

“L, you may not be able to smell your breath, but if I don’t brush mine, you’re going to get a glimpse of what yours smells like.”

“I’m sure it will be fine if it means I don’t have to go through that again.”

“It’s almost like you _want_ me to brush your teeth for you.”

“…”

.o

L crinkled his nose in disgust two days later when he smelled how awful Light’s breath was, not having been able to brush without a toothbrush.

Light was given a new toothbrush, but curiously, there was another toothbrush sitting beside his. L couldn’t be brushing his own teeth now, could he…?

As Light finished his shower before bed and brushed his teeth, he noticed L was not brushing his despite the second toothbrush. Light could only stare at him in honest disbelief.

“You really expect me to brush your teeth for you.”

L smiled.

.o

It turned out Watari was the one who’d been keeping excessive tartar buildup from forming on L’s teeth.

At the end of their first week handcuffed together, Light was startled when L’s head dropped and his face smashed into that nice-looking cake he’d been eating. Light himself had been feeling sleepy, but not enough to fall asleep like _that_.

Watari appeared in the room and looked surprised that Light was staring back at him. Watari never explained what was happening; he just secured Light’s handcuff to a stationary object and took L away.

Light could make inferences, though.

At some interval, Watari knocked L out with some sort of sleeping pills he put in L’s food. Watari would likely then manually clean all of the tartar off of L’s teeth and brushing them. That would explain why L’s teeth looked like they had no cavities or serious tartar buildup. Light wasn’t sure if it was every so many days or weeks, but it was probably every week given that when he brushed L’s teeth for the first time, there wasn’t much plaque there.

Of course, he could only guess, because he had no idea why Watari had taken L away. He had a lot of time to think when he was by himself that night.

The next week this happened, Watari made sure to use stronger sleeping drugs to assure that Light would be knocked out as well for L’s cavity prevention session. The detective may have been an adult legally, but he refused to brush his teeth, even at Watari’s insistence that tooth decay from excess sugar could and would kill the detective once the decay caused infection and said infection travelled into his bloodstream.

He used to brush the boy’s teeth himself, when L was younger, but at a certain point, L refused to allow Watari to brush his teeth. To see on the surveillance cameras Yagami Light brushing his teeth—despite the initial resistance on L’s end—and then _continuing_ to brush his teeth every night then, with decreasing resistance from L, was shocking for Watari.

Maybe he could finally stop having to sedate L to clean his teeth, since the next time L was sedated for his teeth cleaning, there was significantly less tartar buildup for him to clean off. There was still some in the cracks where floss would normally be able to take care of it, but he doubted Yagami Light would ever be able to get L to sit still under his hand long enough to do that.

He had his reservations about Yagami Light but if Yagami Light was able to make an aspect of his job like this easier, then maybe he wasn’t such a bad kid.


End file.
